1. Field of the Invention
The present invention relates to a guide rail assembly for receiving optoelectronic modules therein, wherein the guide rail assembly comprises a plurality of stacked guide rails.
2. Description of the Related Art
U.S. Pat. No. 5,879,173, issued to Poplawski et al. on Mar 9, 1999, discloses a receptacle or guide rail for receiving a removeable optoelectronic module therein. FIGS. 10, 15, and 16 disclose a guide rail 372 having a box configuration, while FIGS. 14, 17 and 18 disclose another type of guide rail. U.S. Pat. No. 5,767,999, issued to Kayner on Jun. 16, 1998, discloses another type of guide rail for receiving a removeable optoelectronic module therein. Both Poplawski et al. and Kayner disclose an electrical connector adapted for electrically engaging with an optoelectronic module received in the guide rail. Both electrical connectors are mounted on a printed circuit board by soldering and do not engage with the associated guide rail, so are not supported by the guide rail. Therefore, when an optoelectronic module mates with these electrical connectors, the mounting tails of the contacts of these electrical connectors are subject to a force by the optoelectronic module which may destroy the connection between the mounting tails and the mounting pads on the printed circuit board.
U.S. Pat. No. 6,047,172, issued to Babineau et al. on Apr. 4, 2000, suggests an arrangement of guide rails in two rows, as shown in FIG. 2 of Babineau. (Note that only one layer is clearly illustrated.) The upper guide rails would be mounted on an upper printed circuit board, while the lower guide rails would be mounted on a lower printed circuit board. Although Babineau et al. suggests the idea of arranging the guide rails in two different levels, the implementation of this idea is not cost effective because two different printed circuit boards are required.
U.S. Pat. No. 6,276,963, issued to Avery et al. on Aug. 21, 2001, suggests a stacked arrangement of guide rails with one guide rail above another guide rail. However, the structures of said two guide rails are different, so it is necessary to manufacture the upper and lower guide rails using two different dies. The implementation is not cost-efficient. In addition, corresponding electrical connectors only mount to a printed circuit board and do not engage with the guide rails; therefore, Avery et al. has the same problem as Poplawski et al.
U.S. Pat. No. 6,272,019, issued to Edwards et al. on Aug. 7, 2001, discloses two GBIC guide rails mounted in back-to-back fashion on opposite sides of a connector plate, as shown in FIG. 3 of Edwards. This solution has complications of its own, and requires inverse insertion of optoelectronic modules therein.
Hence, an improved guide rail assembly which firmly supports connectors contained within the guide rail assembly and which provides convenient and cost effective stacking of two guide rails, one above the other, is desired.
An object of the present invention is to provide a guide rail assembly which firmly supports electrical connectors included therein.
Another object of the present invention is to provide a guide rail assembly in which two guide rails can be stacked one above the other and mounted on the same printed circuit board.
A further object of the present invention is to provide a guide rail assembly in which the structure of each guide rail frame is identical in order to simplify manufacturing.
To obtain the above objects, a guide rail assembly mountable onto a printed circuit board and adapted for receiving two optoelectronic modules therein comprises two guide rails, two electrical connectors, and a mounting device. The two guide rails are identical in construction and can be stacked one above the other using the mounting device. Each guide rail comprises a frame with a metallic cover, a door, and a pair of grounding plates attached to the frame. Each frame has two side beams and a rear beam connecting the side beams, thereby defining a receiving space between the two side beams and the rear beam for receiving an associated electrical connector and for accepting an optoelectronic module therein. Each frame defines a port in a front portion thereof for entrance of the optoelectronic module. The side beams each define a receiving slot in an inner wall thereof. A pair of side lugs is integrally formed on an outside surface of each side beam.
Each electrical connector has a mating portion adapted for mating with the optoelectronic module and a mounting portion adapted for mounting to a printed circuit board. The electrical connectors each have a pair of ribs at opposite sides thereof for engaging in corresponding receiving slots in the side beams of the associated frame. The ribs thereby fix the connectors in the respective guide rails. Further engagement between each electrical connector and its associated guide rail is provided by an ear portion at a top of each connector which engages with a hook formed on the associated metallic cover, which is mounted on the frame of each guide rail. Thus, the two electrical connectors mechanically engage with and are supported by an associated guide rail.
The mounting device comprises four elongate posts and four fastener members. The elongate posts fix a lower of the two guide rails to the printed circuit board by fixing each side lug of the lower frame to the printed circuit board. The elongate posts also elevate the upper of the two guide rails above the lower of the two guide rails. The fastener members fix the side lugs of the upper frame to a top surface of the posts.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a guide rail assembly of the present invention for connecting optoelectronic modules to a printed circuit board;
FIG. 2 is an enlarged, exploded, perspective view of a guide rail of the guide rail assembly of FIG. 1;
FIG. 3 is an enlarged, exploded, perspective view of an electrical connector of the guide rail assembly of FIG. 1;
FIG. 4 is an assembled view of the guide rail assembly mounted onto a printed circuit board.